Diver&#39;s watch



U A. ESCHLE April 14, 1970 DIVER'S WATCH' Filed April 10, 1968 INVENTOR.910/: nmzt BY ,2 MN

Malay-r United States Patent O 3,505,808 DIVERS WATCH Urs Alois Eschle,Le Locle, Switzerland, assiguor to Manufacture des Montres Doxa SA, LeLocle, Switzerland, a body corporate of Switzerland Filed Apr. 10, 1968,Ser. No. 720,102 Claims priority, application Switzerland, Apr. 14,1967,

5,295/ 67 Int. Cl. G04b 19/18 US. Cl. 58126 5 Claims ABSTRACT OF THEDISCLOSURE A divers watch having a rotatable bezel carrying twograduatedscales having a common zero point. One of said scales forms a graduationdividing the circle of the bezel into minutes while the other scalecomprises a graduation and indications referring to diving depths.

BACKGROUND OF THE INVENTION This invention relates to a divers watch ofthe type comprising a rotatable bezel carrying guide marks arranged sothat the position of the minutes-hand of the watch with respect to theguide marks maygive to the diver an indication of time relative to amaximum duration of dive.

Divers Watches of this type are already known in the art. In one ofthese known watches the rotatable bezel is graduated in minutes. Thisgraduation, however, obliges the diver to memorize a rule ofcorrespondence between the reached depths and the limit durations ofdive from which on it will be necessary for him to observe decompressionstops on his way back to the surface. To remove this drawback, which maylead to a positive danger since at great depths the intellectualcapacities of a diver may be substantially reduced, it has already beenproposed to provide the bezel with a depth graduation so that when thezero point or origin of this graduation is placed opposite'theminutes-hand at the beginning of the dive, all the diver has to do. toknow the limit duration is to know at which depth he is and to check themoment where the minutes-hand reaches the position opposite thecorresponding indication of depth of the graduation.

It has also already been proposed, to the same end, to keep a bezelgraduated'in minutes on the periphery of the watch case, and to make theminutes-hand move with a disc carrying a graduation indicating thedepths. In order to use such a watch it is necessary to place the zeropoint of the bezel graduation opposite the indication of the reacheddepth at the moment of the diving. The limit duration of dive at thisdepth is reached when the minuteshand reaches the point at which it isopposite 'the zero point of the bezel. However, while the differentsolutions to the problem indicated above make unnecessary for the diverto memorize a decompression table or a rule, of correspondance betweenthe limit durations of dive on the one hand and the depths on the otherhand these solutions do not enable the diver to read directly on hiswatch -the time interval that has elapsed since he entered the waterunless he had also memorized the exact time at which this eventhappened.

Now the limit duration of a dive may be calculated as a function of thedepth according to different rules. On the other hand occasionally adiver may want to arbitrarily limit his dive to a period that isinferior to the maximum period givenv by a certain table, for example tohalf of the duration given by said table.

Thus the prime object of the present invention is to realize a diverswatch which, while not being of a construction more complicated than theheretofore known watches, and while providing as well as these knownWatches the indications of the limit durations of dive, in additionaffords for the diver to read directly on this watch, the time intervalin minutes which has elapsed since the beginning of the diving.

SUMMARY OF THE INVENTION To this end this invention has for its subjecta divers watch, comprising a rotatable bezel carrying guide marks orindicating graduations arranged so that the position of the minute-handwith respect to the guide marks may give to the diver an indication oftime referring to a maximum duration of dive, in which the guide marksform two concentrically arranged graduated scales comprising a commonzero point, whereby the one of said scales divides the circle of thebezel into minutes, while the other scale comprises a graduation andindications referring to diving depths.

BRIEF DESCRIPTION OF THE DRAWINGS The single figure of the accompanyingdrawing illustrates by way of example in a plan view an embodiment of adivers watch according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawing reference numeral1 designates the casing of a divers watch to which are attached the twoends of a band or strap 2 and the windingbutton 3 of which is partiallyenclosed in a peripheral protecting collar 4. The dial of the watch isof the conventional type provided with horological marks and for thisreason is not shown in detail. It is covered by the glass of the watchand between the glass and the dial there are arranged the usual hands,as the minute-hand 14, the hour-hand 15 and the second-hand 16.

The glass is surrounded by a rotatable bezel 5 which is arranged forrotation by hand in counterclockwise direction. This bezel has itsperiphery provided with a plurality of circumferentially spaced notchesor cut-outs defining teeth 6. As clearly illustrated, the notches thatdefine the circumferentially extending series of outwardly extendingteeth are so formed that the extent of the opposite faces of the teethare different. Thus, the faces 6 of successive teeth on the clockwiseside of the axes of the teeth are substantially radially disposed whilethe faces 6" of successive teeth on the opposite side of the axes ofsaid teeth are inclined toward the respective axes in the clockwisedirection. Thus, the-faces 6 afford or offer a better grip when thebezel is turned in counterin clockwise direction than when it is triedto be turned mediately at the interior of the recessed rim with thecut-outs 6. The zeropoint indicating graduation or origin of thisgraduated scale is marked by a circular recess 8 to which corresponds asmall projection 9 formed on i the periphery of the bezel. Theindicating graduations 10 of the scale 7 are irregularly distributedover the circle of the bezel and are numerical indicia which decrease inthe clockwise direction from 60 to 2.0. Concentrically arranged withinthis graduated scale extends a second scale marked by radial strokes 11which are evenly distributed on the circumference of the bezel 5. Acircular recess 12 arranged on the same radius on the same side of theaxis of rotation of the minute hand 14 as in the recess 8 indicates theorigin or zero point indicating graduation of this second graduatedscale 11 which also carries indications 13 in form of numerical indiciafrom 5 to 55 and spaced 30 from one another. This inner scale thusprovides indicating graduations denoting in minutes the time intervalelapsed from the moment when the minutehand 14 has passed opposite thecommon zero point 12, 8.

As appears from the drawing the numerical indicia 5 of the innergraduated scale coincides with the numerical indicia 60 of the Outergraduated scale, while the numerical indicia 25 and 50 of the firstscale coincide with the numerical indicia 30 and of the outer scale. Thetwo scales thus bring about a relation between the durations and thevertical extent of depths, which relation indicates the limit durationfor which a diver may remain at a given depth without having to observedecompressing stops when returning to the surface. The relation whichresults from the drawing is the so-called American relation.

If the indicating graduations of the bezel 5 would have been made inaccordance with the so-called French scale, the coincidences would bedilferent.

The use of the described watch is exactly the same as that of a watchhaving a bezel 5 carrying only one scale.

Just before the dive the diver rotates the bezel 5 to position theradially aligned point indicating graduations O8 and 12 opposite or inradial alignment with the momentary position of the tip of theminute-hand. From this moment on all the diver has to do is to measureby means of a manometer the depth at which he is and to observe whetherthe minute-hand has already or has not yet reached the correspondingmark of scale 7 corresponding to this depth, to know whether he canreturn to the surface directly or not. But at the same time the positionof the minute-hand with respect to the inner zero point indicatinggraduation 12 of the scale gives him directly the duration of his diveup to this moment without necessity for him to memorize the exact timeat which the diving began.

In order to clearly differentiate the two graduated scales, thenumerical indicia of one of these scales may be marked with a vivid orbright colour, for example orange, while the indicating graduations ofthe other scale could be made in black, for example. If the twoabove-said colours are selected it will be preferable to mark in orangethe numerical indicia and the zero point indicating graduation 8 of theouter scale corresponding to the depths.

What is claimed is:

1. In a divers watch for indicating conditions to a diver, a minutehand, a rotatable bezel radially outwards of the path of movement of thetip of said minute hand, said bezel having two series ofcircumferentially spaced condition indicating graduations defining twoconcentrically arranged graduated scales, each scale having a zero pointindicating graduation, the zero point indicating graduations of therespective scales being in radial alignment on the same side of the axisof rotation of said minute hand, the indicating graduations of the firstof said scales dividing the circular extent of said bezel into minuteswith progressive minute indicating graduations increasing in theclockwise direction from said zero point indicating graduation of saidfirst of said scales, the indicating graduations of the second of saidscales dividing the circular extent of said bezel into vertical extentof depth indicating graduations with said last mentioned indicatinggraduations decreasing in the clockwise direction from the zero pointindicating graduation of the second of said scales, each indicatinggraduation of each scale forming an angle with its associated zero pointindicating graduation and the axis of rotation of said minute hand,whereby upon rotation of said bezel to position said radially alignedzero point indicating graduations in at least approximate alignment withthe radial position of the tip of said minute hand substantially at themoment of the start of a dive, observance during a dive of the extent ofmovement of and the radial position of said minute hand in relation tosaid positioned radially aligned zero point indicating graduationsprovides a direct indication'of the maximum period of time that a divermay remain at the depth then indicated by the radial position of theminute hand with relation to the then radially aligned "vertical extentof depth indicating graduation on the second of said scales without thediver having to observe decompression stops on the way back to thesurface and a direct indication on said first scale of the duration ofdive up to the moment of observance in accordance with the ex-' tent ofmovement of said minute hand.

,2. A divers watch as claimed in claim 1 and the periphery of said bezelhaving circumferentially spaced notches therein defining acircumferentially extending series of outwardly extending teeth eachhaving opposite faces, the faces of successive teeth on the clockwiseside of the axes of said teeth being substantially radially disposed andthe faces of successive teeth on the opposite side of the axes of saidteeth being inclined toward the respective axes in the clockwisedirection so as to afiord a better grip for turning the bezel in acounter-clockwise direction.

, v3. A divers watch as claimed in claim 1 and the indicatinggraduations on each of said scales including colored numerical indiciaand the color of the numerical indicia on one scale being different thanthe color of the numerical indicia on the other scale.

4. A divers watch as claimed in claim 1 and the indicating graduationson the first of said scales including circumferentially spaced minuteindicating numerical indicia progressively increasing in the clockwisedirection and radially extending marks between successive numericalindicia and the indicating graduations on the second of said scalescomprising vertical extent of depth indicating numerical indicia.

' 5. A divers watch as claimed in claim 4 and the numerical indicia onboth scales being colored, and the color of the numerical indicia on onescale being different than the color of the numerical indicia on theother scale.

References Cited UNITED STATES PATENTS 3,124,928 3/1964 Brunet 5 8126 XFOREIGN PATENTS 365,027 11/1962 Switzerland. 436,140 1/1967 Switzerland.

RICHARD B. WILLIAMS, Primary Examiner STANLEY A. WAL, Assistant ExaminerUS. Cl. X.R.,

